S.W. Yusuf

Early results of endovascular aortic aneurysm surgery with aortouniiliac graft, contralateral iliac occlusion, and femorofemoral bypass

PURPOSE The aim of this study was to evaluate the feasibility of endovascular aortic aneurysm repair with use of an aortouniiliac graft secured with self-expanding (Gianturco) stents. METHODS Thirty patients with a median age of 72 years (age range, 52 to 86 years) and aneurysm diameter of 6.0 cm (range, 4.0 to 9.0 cm) were treated with an aortouniiliac endovascular graft. Of these 30 procedures, 28 were carried out electively and two as emergencies for leaking aneurysm. Of the 30 patients, 21 (70%) were considered to be at high risk for open surgery. A modified Gianturco stent, Dacron graft, and Wallstent were used for these procedures. RESULTS Endovascular repair was successfully carried out in 25 of 30 (83.3%) patients. All these patients were mobile and had resumed a normal diet within 48 hours of the procedure. The overall 30-day mortality rate was two in 30 (6.6%), but it was one in 28 (3.5%) for the elective cases; all deaths occurred in the group at high risk for surgery. Other complications encountered within 30 days of procedure included myocardial infarction in one patient, pneumonia in two patients, homonymous quadrantanopia in one patient, and colonic ischemia in one patient, giving an overall morbidity rate of four in 30 (13.3%). At a median follow-up of 4 months (range, 1 to 13 months), 27 of 30 (90%) patients remain alive and well. CONCLUSION Endovascular aortouniiliac repair of abdominal aortic aneurysm with Gianturco stent is feasible in both elective and emergency situations. It appears to be minimally traumatic, and the majority of patients deemed to be at high risk for open surgery can safely undergo endovascular repair. However, data on more patients with longer follow-up is required to determine its role in the management of abdominal aortic aneurysm.

Transfemoral endoluminal repair of abdominal aortic aneurysm with bifurcated graft

Traditional open repair of abdominal aortic aneurysm has disadvantages. We present our experience of transfemoral endoluminal repair with a bifurcated graft system. 29 patients with aortic aneurysm over 5.5 cm in diameter and 1 with a 3.2 cm aneurysm and bilateral iliac stenosis were assessed; 5 were suitable for the procedure. The operation was successful in all the patients, without haemodynamic compromise or major complications. This technique has the potential to reduce morbidity and mortality from abdominal aortic aneurysm. Further modifications are required to make it applicable to most aneurysms.

A study on the patency of the inferior mesenteric and lumbar arteries in the incidence of endoleak following endovascular repair of infra-renal aortic enerysms

OBJECTIVE An endoleak is defined as the presence of contrast medium within the aneurysm sac on post-operative contrast-enhanced computed tomography scans (CT) in patients following endovascular repair (EVR) of abdominal aortic aneurysms (AAA). The aim of this study was to correlate the incidence of endoleaks with the presence of patent lumbar (LA) and inferior mesenteric arteries (IMA) as seen on pre-operative angiography. DESIGN, MATERIALS AND METHODS Forty-seven patients were assessed pre-operatively by both CT and angiography by a blinded radiologist prior to EVR of AAA. The number and size of patent vessels was recorded and correlated with the incidence of LA or IMA endoleaks on follow-up CT. Patent lumbar vessels were scored: 1 = small, 2 = medium, 3 = large. RESULTS Five patients were noted to have patent IMA on pre-operative angiography but none developed an endoleak. In this series, five patients had an endoleak due to a patent LA. The median score for patients with no endoleak was 1 (0-9) and for those with a lumbar endoleak 2 (0-5) (P = 0.26, Mann-Whitney U-test). The number of patent lumbar arteries was not predictive of a subsequent endoleak. Two out of nine (22 %) patients with large patent LA subsequently developed an endoleak. If a policy of pre-operative embolization on the basis of large patent LA had been adopted, seven patients would have had an unnecessary invasive procedure. CONCLUSION Pre-operative angiography to look for patent LA and IMAs is not required in patients undergoing EVR or AAA.

The anatomy of abdominal aortic aneurysms: Implications for sizing of endovascular grafts

OBJECTIVE To determine the full range of aorto-iliac anatomy of patients with abdominal aortic aneurysms (AAAs) and thence the range of endovascular graft sizes required to deal with the majority of AAAs. DESIGN Analysis of preoperative spiral CT measurements. MATERIALS One hundred and sixty-eight patients with AAAs. METHODS Multiplanar reconstruction measurements were taken of proximal aortic neck diameter and length, lowermost renal artery to the aortic bifurcation distance and length and diameter of common iliac arteries. Based on these measurements a range of graft sizes that would fit the majority of AAAs was determined. RESULTS Ranges of anatomical variables were as follows: proximal aortic neck diameter 18-30 mm, renal artery to aortic bifurcation distance 93-210 mm, common iliac artery length 13-108 mm, common iliac artery diameter 6-67 mm. Over 750 graft sizes would be required to cover all anatomical combinations using a one-piece aorto-uni-iliac graft. CONCLUSION A wide variety of aorto-iliac anatomy exists in patients with AAAs. The large number of graft sizes required to deal with the majority of AAAs makes the production of one-piece endovascular grafts commercially impractical. A proposed two-piece modular graft would allow the majority of AAAs to be treated using only 16 graft sizes.

Stent-graft migration after endovascular repair of abdominal aortic aneurysm.

Purpose: To report the incidence of graft migration in patients after endovascular repair of abdominal aortic aneurysms (AAA) and assess the significance of neck diameter changes in patients with and without suprarenal stent implantation. Methods: The medical records and imaging studies of 176 consecutive patients (175 men; median age 71 years, range 48–88) who had endovascular AAA repair with the Nottingham aortomonoiliac system were reviewed. The following parameters were recorded: preoperative neck diameter and length, presence of intraoperative and late graft migrations, time to onset of late migration, length of late migration, and neck diameter changes in patients with documented late graft migration. The patients were divided into 2 groups based on the placement of an endograft with or without suprarenal bare stent fixation. Median follow-up was 15 months (range 1–48). Results: There were 15 (8.5%) graft migrations (6 intraoperative and 9 late). Of those, 14 (10.9%) were in the 128-patient infrarenal fixation group and 1 (2.1%) in the 48-patient suprarenal stent group. Median neck diameters on preoperative and postoperative computed tomography scans in patients with late migration were 22.2 mm and 23.0 mm, respectively (p>0.05). The median time to graft migration was 14 months after the original operation (range 6–36). Conclusions: Distal device migration occurred frequently with the Nottingham system. Late graft migration was not associated with neck enlargement. Endografts with a suprarenal stent may have a decreased incidence of graft migration.

Prospective randomised comparative study of pulse spray and conventional local thrombolysis.

OBJECTIVES To compare the time required to achieve lysis with the pulse spray technique and the conventional slow continuous infusion technique. DESIGN Prospective randomised open Study. METHODS Eighteen patients suitable for intra-arterial thrombolytic therapy with conventional and pulse spray technique were randomised 1:1 to receive either pulse spray thrombolysis with 0.33 mg/ml rt-PA injected as a bolus of 0.2 ml or conventional thrombolysis with 0.05 mg/ml rt-PA infused at a rate of 10 ml/h. RESULTS The age, duration of symptoms, length of occlusion and prethrombolysis ankle brachial pressure index were comparable in the two groups. The median duration of thrombolytic therapy in the pulse spray group was 195 min (range 90-1260) compared to 1390 min (range 300-2400) in the Conventional group. The difference between the two groups was significant, p < 0.002 (Mann-Whitney test). CONCLUSIONS Significantly shorter time is required to achieve local thrombolysis with pulse spray compared to the conventional infusion method.

Carbon dioxide: An alternative to lodinated contrast media

OBJECTIVES To study the use of carbon dioxide as a contrast medium for arteriography. METHODS Carbon dioxide was used as a contrast medium for intra-arterial digital subtraction lower limb angiography in 12 examinations on 11 patients. RESULTS No complication was encountered and no significant changes occurred in the arterial pH, PaCO2 and PaO2. The quality of images as assessed by an independent observer was adequate for the majority of the vessels (77%). CONCLUSIONS Carbon dioxide is a safe alternative in patients at an increased risk of adverse reaction to iodinated ionic or non-ionic contrast medium and is very cheap.

A 10-year follow-up of patients presenting with ischaemic rest pain of the lower limbs

OBJECTIVES To determine the 10-year outcome of patients presenting with rest pain. METHODS One hundred and three consecutive patients presenting with ischaemic rest pain in 1987 were followed up after 10 years. Hospital notes, death certificates and telephone interviews with patients were used to determine outcome. RESULTS Follow-up data is available for 97 (94%) patients. Thirteen patients are alive (13.7%) after 10 years, 12 presented with rest pain alone and one had ulceration. Three of these had amputation. The commonest cause of death was myocardial infarction (n = 21, 25%). In those who had died, the median age of onset of symptoms was 72 years (49-93) for rest pain, 74 years (56-87) for ulceration and 71.5 years (45-85) for gangrene. Their survival after admission was a mean of 39 months with rest pain, 33 months with ulceration and 42 months with gangrene. The overall 5-year survival was 31% and the 10-year survival 13%. CONCLUSION Patients presenting with ischaemic rest pain have a poor prognosis. The presence or absence of ulceration or gangrene does not influence the outcome. Most patients die from smoking-related diseases.

Experience with pulse-spray technique in peripheral thrombolysis.

Pulse-spray thrombolysis (PST) is a new technique of accelerated peripheral arterial thrombolysis. This technique has been evaluated on 24 patients with limb ischaemia. Severe acute limb-threatening ischaemia with sensory and motor deficit was present in 11/24 (45.8%) patients. The median dose of recombinant tissue plasminogen activator (rt-PA) used was 18 mg (10-35 mg) injected in a concentration of 0.33 mg/ml and bolus size of 0.2 ml. The median length of occlusions treated was 23 cm (range 4-55 cm). Complete initial lysis was achieved in 23/24 (95.8%) and limb salvage at 30 days was achieved in 18/24 (75%) of the cases. The overall 30-days mortality was 4/24 (16.6%) and 2/4 (50%) in those who required surgical intervention. The median duration of thrombolytic treatment was 137.5 minutes (range 35-1125 minutes) which is an 11-fold and significant reduction (p < 0.001, Mann-Whitney) in lysis time compared with the results of conventional low dose infusion of rt-PA at a rate of 0.5 mg/h in 120 consecutive patients in our unit. PST rapidly restores vascular patency and may become the treatment of choice for acute limb ischaemia including those at immediate risk of irreversible ischaemic injury which would not be considered suitable for conventional thrombolysis.

Intrarenal color duplex examination of aortic endograft patients with suprarenal stents.

PURPOSE To report an experience using intrarenal color duplex ultrasonography (ICDU) to detect high-grade renal artery stenosis in patients who had endovascular repair of abdominal aortic aneurysm (AAA) with suprarenal stent fixation. METHODS Twenty-eight patients (25 men; mean age 71 years, range 58-83) who had endovascular AAA repair with suprarenal stenting at least 3 months prior to commencement of this study were screened with ICDU. Acceleration time (AT), peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive index (RI) were measured. The Doppler waveform was quantitatively scored on a scale from 0 to 4. AT >0.07 seconds, RI <0.45, or a Doppler waveform score of 0 or 1 (indicating loss of early systolic peak) were indicative of high-grade renal artery stenosis. RESULTS Median follow-up was 15.5 months (range 3-34). ICDU was successful in 54 (98%) of 55 kidneys scanned. No AT values exceeded 0.07 seconds, all RIs were >0.45, and no waveforms had loss of early systolic peak, indicating that no patient had evidence of high-grade renal artery stenosis. CONCLUSIONS ICDU is a simple and affordable method that seems well suited to periodic screening in patients with suprarenal stents. Longer follow-up with a larger number of patients is needed before definite conclusions can be drawn about the effect of suprarenal stenting on renal circulation.